使用OWL-API和Hermit打印Pizza本体的超类

Question

I try to print the Superclasses of standard Pizza ontology downloaded from here . I am using OWL API 3.4.3 and Hermit 1.3.8.1 (reasoner).

The following code snippet is used to print the required Superclasses of class "Food" .

OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
IRI ontologyIRI =IRI.create("file:/D:/pizza.owl.xml");      
//IRI ontologyIRI =IRI.create("http://www.co-ode.org/ontologies/pizza/pizza.owl");

OWLOntology ontology = manager.loadOntology(ontologyIRI);
OWLReasoner reasoner = new Reasoner.ReasonerFactory().createReasoner(ontology);
OWLDataFactory df = manager.getOWLDataFactory();    
    try{
            reasoner.precomputeInferences(InferenceType.CLASS_ASSERTIONS);
            //following Lines are to see super classes of Container
            OWLClass clsA = df.getOWLClass(IRI.create(ontologyIRI + "#Food"));
            Set<OWLClassExpression> superClasses = clsA.getSuperClasses(ontology);
            System.out.println("in TRY 1");
            //System.out.println("Hello World\n"+superClasses.iterator().toString());
            for (OWLClassExpression g : superClasses) {
                 System.out.println("The superclasses are:"+g);   
            }
        }
        catch (Exception e) {
            e.printStackTrace();
        }

I do not get any compilation error. The result is in TRY 1 . The content inside for loop has not been printed .

In protege 5.0, I have seen two Superclasses of Food class ; namely DomainConcept and owl:Thing . Why these two names has not been printed by the program?

Where am I doing wrong?

Thanks for any kind of help.

Answer 1

Your ontology IRI is a local file name. When you use it to obtain a class IRI, you're getting a different IRI from the one actually used in the ontology. Check what IRI the class actually has and that should fix your issue.